Title says it all...whats the difference? and also what are the best brand of headers for a decent amount of money...decent i mean 400-500 maximum.

 

All that means is that the 160 stat will open at 160, and the 180 will open at 180. This does not mean that the engine will run at that temperature, as the PCM will have to be updated to turn on the fans at the proper temperature to go with the stat you are using. Theorethically, running the engine at a cooler temp should give a few extra horses, but what really makes a difference is the temperature of the air being sucked into the engine.

As for headers, go on the web and hunt around, but basically you are going to get what you are paying for. I suggest going for a known name brand with some sort of warranty against warping, and rusting or burning out.